Well surveying instrument



July 7, 1953 J. c. HEwlT-r, JR 2,644,242

I WELL SURVEYING INSTRUMENT I Filed Feb. 2s, 1949 Wwf. 20 N .02. y if 32f/)v @lgn/,77;

l jg y INVE 0R ATTORNEY.

Patented July 7, 1953 UNITED YsrArss earl-.ENT oFFlcr.A

2,644,242 WELL SURVEYING INSTRUMENT John C. Hewitt, Jr., Long Beach,Calif.

Application February 28, 1949, Serial No. 78,713 A This invention has todo generally with. instruments for indicating or recording the positionof a .float-carried marking or index, and is directed particularly toimprovements in orienting instruments employing a magneticallyresponsive (e. g. compass) float positioned between a vertically spacedlight source and a light sensitive recording means, whereby the floatposition is recordable by transmission of light through the float.

One of my primary objects is to provide an instrument of the typeemploying a translucent iioat, whereby it is made possible to transmitthe light beam free from interference through the vertical axial centralportion of the float, and in so doing to effect recording illuminationof the oat with relation to a stationary marking located substantiallyin alinement with the normal vertical axis of the float.

Particularly contemplated in conjunction with light projection throughthe central portion of the float, is the use of float guide or centeringmeans radially offset from the float axis so that its center remainsunobstructed against light passage. t is found that centering ofl thefloat by maintaining about its axial light-passing portion a liquidmeniscus barrier against radial displacement of the oat, as in themanner more particularly dealt with in my copending application SerialNumber 24,761, led May 3, 1948, on lnstrument Float Control, now PatentNo. 2,500,411, serves most eifectively to accommodate the float to therequirements of a recording instrument.

In accordance with a preferred, though typical, construction, atranslucent compass float carrying directional indicia is contained in atranslucent chamber below a light source in axial alinement with thefloat, and from which light is projected downwardly through the iioat,liquid and chamber to a recording means, e. g. film, below.

Interposition between the iloat and lm of a ref-` erence markingstationary with reference to the chamber and alined with the normalvertical axis of the float, enables the record to show both theinclination of the instrument and the direction of the inclination. Thefloat is centered in the chamber by a light passing guide depending fromthe top of the chamber below the liquid level therein so that the liquidforms an annular meniscus about and adjacent the surface of the guide.By shaping the float as hereinafter described and closely relating thespecific gravity of the float to the liquid density, the float is causedto engage against the under side of the liquid meniscus which thusbecomes a centering barrier for the float.

9 Claims. (Cl. 33-205.5)

All the various features and objects of the inyention, as well as thedetails of an illustrative embodiment will be fully understood from thefollowing description of the accompanying drawing, `in which:

Fig. l is a general view showinga typical-form of the invention asembodied in a well surveying instrument; v

Fig. 2 is a view taken from line 2 2 of Fig. l showing the oat bottommarkings;

Fig. 3 is a View taken from line 3 3 of Fig. l showing the stationaryreference marking;

Fig. 4 is a fragmentary view illustrating the float and guide relationin an inclined position of the instrument; and

Fig. 5 is a fragmentary sectional View illustrating a variationalembodiment of the invention.

It will be understood that with respect to various features, thedetailsof which are not essential to the present invention, the showingin Fig. 1 is a diagrammatical. As illustrative of the invention, theinstrument is shown to comprise a tubular case l0 having upper and lowersections Il and l2 interconnected at the joint I3.

Section Il of the case contains a oat cham-l the manner disclosed in mycopending application Ser. No. 24,761, referred to above.

The float is shown to have the form of a translucent or transparenthollow body l l, to the interior of which the liquid I6 is accessiblethrough openings I8. The float may carry in any appropriate manner amagnetized element, as for example the ring I9, serving as a compassneedle for maintaining the float oriented to the ear-ths magnetic polesor other external field. As illustrated in Fig. 2, the bottom surface 20of the float may carry the illustrated directional indicia and theconcentric circle angle-indicating markings.` The top of the floatcontains a circular or cylindrical opening 2l immediately about which isasmall dimension upstanding annularl rim 22, the outer surface of whichextends angularly and -inwardly to intersect the wall of opening 2l.

The float il may be made of any suitable material, such as a clearorganic plastic, capable of transmitting light from the light sourceytothe recording means. The float chamber I4 contains a body of liquidi6, such as perchlorethylene or any other suitable liquid, havingproper` specific gravity relation to the float. Generally speaking, theiloat material and liquid may be selected with relation to theirspecific gravities so that ythe float will remain immediately below oradjacent to the liquid surface. Assuming the liquid to beperchlorethylene having a specic gravity of about 1.6, the oat materialmay be selected to have a specific gravity of about 1.2 to 1.5.

The top of the oat chamber is formed by a transverse wall 23 carrying acylindrical guide 24 depending below the surface of the liquid IS inaxial alinement with the iloat chamber. As illustrated, the liquid formsadjacent the wall of the guide 24 an annular meniscus 25, the under orconvex side of which is engaged by the float rim 22. The relationbetween the meniscus, float rim and the size of opening 2| is such thatthe meniscus presents a barrier against lateral displacement of thefloat from accurately centered position in. the chamber, and undernormal conditions of use, against engagement of the float with the sideof the guide. Preferably the guide is formed as a tube to contain theliquid I6 at its chamber level in all positions of the instrument.

A light source, such as lamp 26 and which may be supplied with currentfrom any source, typically the battery 21, is carried by support 28above the float chamber and in axial alinement with the guide tube 24.Light rays from the lamp pass downwardly through the tube, float and thetranslucent or transparent chamber bottom l5, the latter carrying areference marking 29, see Fig. 3, having its center coincidentV with thechamber axis. Below the float chamber, a lens 3B directs the transmittedlight rays to an appropriate light-sensitive recording means, such asthe diagrammatically illustrated lm disc 3| carried by support 32 withinthe lower section I2 of the case.

As will be understood, should a record be taken by brief illumination ofthe lamp 2B using any conventional type of energization control, notshown, with the instrument in true vertical position, the lm 3| wouldrecord the indicia carried by the iloat surface 2|) and the relativelystationary marking 28 in superimposed and axially centered alinedrelation. When a record is taken with the instrument in inclinedposition, as in Fig. 4, the centered position of the image of themarking 29 recorded on the lm of course `is unaffected by theinclination, but the superimposed image of the float-carried indicia isshifted relative to the image of the marking 29, to a degree and in adirection (both of which obviously are shown by the character of themarkings on the oat surface 2|!) in accordance with the degrees anddirection of the inclination.

In Fig. I have illustrated a variational embodiment of the inventiondiffering from the previously described form with respect to the oat,guide and float chamber assembly which has the same general relation tothe light source 26, lens 30 and recording means 3| described withreference to Fig. l. In the variational form, the float chamber body 35contained within the instrument case 36 is shown to comprise a pair ofsections 31 and 38 suitably held together in fluid tight engagement, asbetween rings 39, the chamber sections having latched hemisphericalcavities 4B and 4| which together form the iloat chamber 42. Here thefloat guide 43 is shown to be of light-passing tubular form having aspherical 4 bottom end M, the lower portion of which depends below thelevel of the oat chamber liquid 45.

The float in this instance consists generally of a hemispherical andtransparent plastic body 46 having substantially hemispherical topcavity |51 receiving the bottom portion '34 of the guide tube. The floatcontains a suitable arrangement of passages [i8 through which the liquidl5 is accessible to the cavity 2l. The section of the top surface of theiloat with the wall of cavity il is dened by an upstanding annular rim49 which engages against the underside of the liquid meniscus 50 tomaintain the oat in axially alined relation with the guide, as in themanner explained with reference to the centering of the float in Fig. l.The oat-carried polar magnetized compass element or needle is showntypically to be in ring form 5| placed concentrically in the top surfaceof the iloat.

. Aswill be understood, the bottom surface of the float may carryindicia, similar to those illustrated in Fig. 2. The relativelystationary reference marking 52, corresponding to 29 in Fig. 3, may beapplied to a glass window 53 centrally positioned in the bottom of theoat chamber and through which light passing from the lamp 26 through theguide tube d3, oat 46 and the liquid 45, is transmitted to the lens andrecording means below.

It will be understoodthat the drawing is to be regarded merely asillustrative of the invention in certain of its typical embodiments andthat various changes and modifications may be made without departurefrom the ,invention in its intended spirit and scope.

I claim:

l. A direction indicating instrument comprising a chamber containing abody of liquid, a translucent magnetically responsive fioat carried bythe liquid between vertically spaced locations and having a translucentcentral portion at substantially its central vertical axis through whichlight may pass, said liquid forming a meniscus extending annularly aboutand radially spaced from the vertical axis of the float and engaging thefloat to center it in the chamber, a light source mounted stationarilyat one of said locations, means directing ilight from said sourceVertically through the center of said annular meniscus and through saidtranslucent vertical axial central portion of the iloat, meansstationary with relation to said chamber and p-roviding a referencemarking normally and substantially in alinement with the float axis, andlight sensitive means at the other of said locations for recording theoat position with relation to said marking.

2. A direction indicating instrument comprising a chamber containing abody of liquid, a translucent magnetically responsive float carried bythe liquid and having a translucent central portion at substantially itscentral vertical axis through which light may pass, said liquid forminga meniscus extending annularly about and radially spaced from thevertical axis of the float and engaging the float to center it in thechamber, a light source mounted stationarily above and in substantialalinement with the vertical axis of the float, means directing lightfrom said source downwardly through the center of said annular meniscusand through said translucent central portion of the float, meansstationary with relation to said chamber and providing below the oat insubstantial alinement with its normal vertical axis a reference marking,and light sensitive means below said marking for recording the floatposition relative thereto.

3. A direction indicating instrument comprising a chamber containing abody of liquid, a translucent magnetically responsive iloat carried bysaid liquid and having a translucent central portion at substantiallyits central vertical axis through which light may pass, said liquidforming a meniscus extending annularly about and spaced from the floataxis and engageable by the iloat to center the float in the chamber, astationarily mounted light source, and means directing light from saidsource vertically through the center of said annular meniscus andthrough said translucent vertical axial central portion of the oat.

4. A direction indicating instrument comprising a chamber containing abody of liquid, a translucent magnetically responsive float carried bysaid liquid, a guide depending from the top of the chamber, said liquidforming adjacent the surface of said guide an annular meniscusengageable by the float to center the oat about the guide, and a :lightsource above the chamber and from which light is projected through saidguide and the float.

5. A direction indicating instrument comprising a chamber containing abody of liquid, a translucent magnetically responsive float carried bysaid liquid, a tubular guide depending from the top of the chamber belowthe liquid level therein, said liquid forming adjacent the surface ofsaid guide an annular meniscus engageable by the float to center thefloat about the guide, and a light source above the chamber and fromwhich light is projected through said guide and the float.

6. A direction indicating instrument comprising a chamber having atranslucent bottom and containing a body of translucent liquid, atranslucent magnetically responsive compass float carried by the liquidand having indicia to ndicate the iioat polarity, a guide depending fromthe top of the chamber below the liquid level therein, said liquidforming adjacent the surface of said guide an annular meniscusengageable by the float to center the iioat about the guide, a lightsource above the guilde and from which light is projected through theguide, float, liquid and chamber bottom, means below the float providinga reference marking normally and substantially in alinement with thevertical axis of the float, and light sensitive means below said markingfor recording the relative positions of said float indicia and marking.

7. A direction indicating instrument comprising a chamber having atranslucent bottom and containing a body of translucent liquid, atranslucent magnetcally responsive compass float carried by the liquidand having indicia to indicate the iioat polarity, a guide dependingfrom the top of the chamber below the liquid level therein, said liquidforming adjacent the surface of said guide an annular meniscus and theiioat having an annular upstanding rim submerged in the liquid andengageable against the under side of said meniscus to center the floatVabout the guide, a light source above the guide and from which light isprojected through the guide, iioat, liquid and chamber bottom, meansbelow the float providing areference marking normally and substantiallyin alinement with the vertical axis of the float, and light sensitivemeans below said marking for recording the relative positions of saidiioat indicia and marking.

8. A direction indicating instrument comprising a chamber having atranslucent bottom and containing a body of translucent liquid, atranslucent magnetically responsive compass iioat carried by the liquidand having indicia to indicate the oat polarity, a tubular guidedepending from the top of the chamber below the liquid level therein,said liquid forming adjacent the surface of said guide an annularmeniscus and the float having a hollow interior containing the chamberliquid and having also an annular upstanding rim submerged in the liquidand engageable against the under side of said meniscus to center theiloat about the guide, a light source above the guide and from whichlight is projected through the guide, iioat, liquid and chamber bottom,means below the oat providing a reference ymarking normally andsubstantially in alinement with the vertical axis of the float, andlight sensitive means below said marking for recording the relativepositions of said float indicia and marking.

A9. A direction indicating instrument comprisingV a chamber containing abody of liquid, a translucent magnetically responsive float carried bysaid liquid and having a translucent central portion at substantiallyits normal central vertical axis, said liquid forming a meniscusextending annularly about and Aradially spaced from the normal verticalaxis of the oat and engaging the float to center it in the chamber, alight source mounted stationarily at a location to pass light verticallythrough the center of said annular meniscusv and'through saidtranslucent vertical :axial central portion of the oat, means forming areference marking positioned stationarily along the path of lightthrough said oat, a marking on the float, and light sensitive means inthe path of light directed through the float and acting to record therelative positions of said float and stationary markings.

JOHN C. HEWITT, JR.

References Cited in the iile of this patent UNITED STATES PATENTS

